Collection equipments for separating dust, dirt and similar material from air, such as vacuum cleaners, require the use of filter, dust bags or containers for the material to be filtered and collected.
Theses conventional dust bags combine the functions of filtering and collecting. They can consist of paper, or any other filtration type material which on the one hand allows to collect dust and dust-like material and on the other hand has a porosity sufficient for the fluid carrying the dust or dust-like material with a minimum pressure drop. They are light and flexible.
Typically these dust bags are provided with an intake opening through which the dust or dust-like particles is to be transported and collected within the bags. The dust or dust-like material is packed into a bag and then the filled bag is disposed. A dust bag minimizes opportunities to contact collected dust by hand directly. A filter material is opaque normally to prevent people from watching the filling situation of dust bag directly. As long as the accumulation of dust, some methods are necessary to measure when it is time to replace the filled bag. In all of known filterable bag designs the replacing of filled bag is dependent on pressure differences measured.
The bag-less technology separates the functions of collecting and filtering. Normally a durable filter or a cyclone device is used to filter dust air and dirt, and trap dust and dirt in a surrounding transparent container. These containers can be made from strengthened plastic, or any other strengthened lighter and transparent type container material. Dirt and dust are seen and then a filled transparent container will be picked out of position from a vacuum cleaner. These filters can consist of paper, or any other filtration type material which form airflow path and trap dust. The cyclone separating technology has the advantage of collecting coarse particle and a disadvantage on filtering fine particles. A conventional filter can be combined into a cyclone type cleaner for increasing the capacity of collecting fine particles. Durable filters or washable filters are to be cleaned or replaced in a designed long period in most of bag-less vacuum cleaner. Sooner or later there still are some opportunities to touch dirty filters directly.
A need is identified for a way to retain the advantages of flexible filterable bags and transparent bag-less containers; and to reduce the disadvantages affection of no transparent filterable material and touching dirty durable filters.